Human scent matching using specially trained dogs

Abstract

Abstract. The purpose of this project was to provide data on the success rate of dogs identifying people by scent when working in conditions similar to those used by the police in Holland and Germany. Over 700 scent samples were collected from people of both sexes and a wide age range and seven dogs, Canis familiaris, were trained to match human body scents. The test conditions were carefully controlled to eliminate any cue other than the body scents presented to the dog. Each dog sniffed a piece of cloth which had been in contact with an unspecified part of the body of a person and then indicated which of a selection of blank or body-scented cloths bore the same scent. The handler did not know the location of the target scent. The average score of the dogs working with body-scented cloths from six donors was 80% correct whereas a random choice of cloth would have been 17% correct. A further experiment was carried out in which three dogs were asked to match odour from various parts of the body with hand odour of the same donor collected on clean steel tubes. The average score for this task was 85% correct with a selection of six donor odours. The results show that dogs have considerable scent matching ability but that individual aptitude and the day-to-day performance can vary. Dogs used in criminal investigations should be selected for aptitude and the tests replicated so that conclusions are not based on trials from a single dog.